Movement Patterns in a Uruguayan Population of Melanophryniscus montevidensis (Philippi, 1902) (Anura: Bufonidae) Using Photo-Identification for Individual Recognition

The study of the patterns of movement is required to obtain knowledge of different aspects of the natural history of organisms, including foraging sites, shelter, breeding, capability of dispersion, and migration distance. This study analyzed the pattern of movements of a population of Melanophryniscus montevidensis among five sites selected in Barra de la Laguna de Rocha, Uruguay. Sixteen field trips were undertaken between September 2011 and February 2013. Active searches were conducted in every site, and individuals were captured, sexed, measured, weighed, photographed, and released. Photo-identification was used to identify captured (n = 1,594) and recaptured (n = 244) individuals. Photographs were assessed using the software Wild ID. The greatest number of captures and recaptures coincided with the months of breeding activity for the species. There was a significant correlation between body size and distance covered (R-2 = 0.06; P = 0.003). Among the recaptured individuals, 18.9% moved among sites. Most of the individuals that moved either among or inside the same sites (71.8%) covered distances < 100 m. No association was found between the time of recapture and the distance covered (R-2 = 0.01; P = 0.12). Additionally, some individuals were found at the same specific capture zones in subsequent field trips. The results demonstrate the high site fidelity of this species. Such information is essential to estimate the effects of habitat fragmentation in wild populations, as individuals would not be able to change their habitats easily.